GB657875A - Improvements relating to rotors or the like made from at least two sections connected together by annular weld seams - Google Patents

Abstract

657,875. Making turbines. SULZER FRERES SOC. ANON. March 22, 1949, No. 7720. Convention date, April 21, 1948. [Classes 83 (ii) and 83 (iv)] Uniting by fusion.-In a method of welding sections of turbine rotors and the like along annular seams the parts are first tack-welded and then welded between the tacks in a furnace which is at a temperature below the welding temperature, the tack welds and ends of the welding runs being then removed and the gaps thus produced being finally welded. Two adjacent sections 5, 6, Fig. 2, of a turbine rotor are centred at cylindrical faces 7 by a ring 8 and are axially located by removable pins 18 in the ring, so as to provide spaces 9<SP>1</SP> between the parts 5, 6 which close when the welds 10 finally contract. The pins are removed after the tack welds are made and the rotor is inserted in the furnace for completion of the welding. Closable apertures are provided in the furnace wall to permit access to the work which is slowly rotated during welding. Abutments 17 engage when the rotor is assembled and are deformed as shown in Fig. 3 during final contraction. In a modification, faces 14, Fig. 4, and the deformable flanges 17 may abut a locating-ring 13 which centres the sections on its outer face 12. An even number of uniformly-spaced tack welds is preferable, diametrically opposite tack welds being made simultaneously and in welding between the tack welds the next succeeding run is made between the diametrically opposite pair. Further welding runs may be made over the first and the whole may be finally heat-treated.